def create_straightRF
    model = Sketchup.active_model
    prompts = ["长度","直径"]
        defaults = ["3000","25"]
        input = UI.inputbox(prompts, defaults, "创建钢筋直料")
    group = model.active_entities.add_group
        entities = group.entities
    points = [
            Geom::Point3d.new(0,   0,   0),
            Geom::Point3d.new(input[0].to_f.mm, 0,   0)
        ]
    dia = input[1].to_f.mm
    edges = entities.add_line points[0],points[1]
    vector = Geom::Vector3d.new 1,0,0
    vector2 = vector.normalize!
    face = entities.add_face(entities.add_circle points[1], vector2, dia/2)
    face.followme(edges.all_connected)

end
